Features: late-spring or summer flowers, foliage, spiny fruit
Few trees available to northern gardeners will stop viewers in their tracks as quickly and assuredly as A. x carnea ‘Briotii,’ in bloom, unless perhaps your taste toward spectacular blooming trees is more attuned to the sublime A. hippocastanum (Common horsechestnut). Aesculus is a diverse group of extremely attractive trees and shrubs featuring unusual, often rugose foliage, billowing forms and wide options in size, habit, and bloom color. As is always recommended, note the proper botanical name (Aesculus) in your research and shopping; both common names “Buckeye” and “Horsechestnut” are bandied about in the trade.
Little pruning is required. Remove wayward branches in winter or early spring.
The smaller, shrubbier buckeyes are useful in a space-restricted setting, where they can be used as specimens, in shrub or mixed borders or in mass plantings to fill unused corners or to cover hard-to-mow banks.
All parts of Aesculus plants, especially the seeds, are toxic. People have been poisoned when they confused the nuts of these trees with edible sweet chestnuts (Castanea species).
A. x carnea (red horsechestnut) is a dense, rounded to spreading tree that grows 30–40' tall, with equal spread. It is smaller than common horsechestnut but needs more regular water in summer. Spikes of dark pink flowers are borne in late spring and early summer. ‘Briotii’ has large, lobed leaves and stunning red flowers in spring. It grows 25–40' tall, with an equal spread. This cultivar is hardy in Zones 5–9. ‘O’Neill’ grows slowly to 35' in height and 25' in spread. It bears bright red flowers. (Zones 4–8)
A. glabra (Ohio buckeye) is a rounded tree with a dense canopy. It grows 20–40' tall, with an equal spread. The flowers are not very showy and the fruit is not as spiny as that of other buckeyes. This species is susceptible to scorch and will look best when grown in damp, naturalized conditions, such as next to a stream or pond. This species is native to Illinois . (Zones 3–7)
A. hippocastanum (common horsechestnut) is a large, rounded tree that branches right to the ground if grown in an open setting. It grows 50–80' tall and spreads 40–70'. The flowers, borne in spikes up to 12" long, appear in late spring; they are white with yellow or pink marks. ‘Baumannii’ bears spikes of white double flowers and produces no fruit. (Zones 3–7)
The above reprinted with publisher’s permission from Don’s newest book, Tree & Shrub Gardening in Minnesota and Wisconsin.
Here’s an upright, bold evergreen tree that was made for residential landscape use. Found as a chance seedling in northern Minnesota, ‘Norway Compact’ will eventually grow to 30-40’ while maintaining a bubbling, rounded, relatively narrow width of 15-20’. An exceptional tree for mixed evergreen and deciduous borders and foundation plantings.
It has proven to be resistant to winter burn. Like virtually all pines, it prefers well-drained soil with a neutral to slightly acidic pH. Full sun. Hardy to USDA Zone 2.
An attractive landscape is all about using plants with compelling foliage. That’s the key to ‘CG’ and the big reason I’ve been including it in my designs for the past three years.
The semi-evergreen shrub features light green leaves with wide, yellow margins. The medium to small, oval leaves hang tightly to the long, arching branches. The plant can be pruned to stay tight in appearance, or allowed to spread. Mature height is 4’ tall by 3’ wide.
The shrub performs well in full sun to partial shade. It isn’t particularly picky about soil, though neutral to slightly acidic soil is best. Fertilize in spring, water no more or less than average for shrubs, and it will flourish.
Spring flowers are insignificant, but with May through November foliage that looks like this, who cares? The plant will retain its leaves most winters. Hardy to Zone 4.
What’s in brilliant bloom right now across the northland? Actea, a tall, magnificent perennial that thrives in part shade. In fact, plants bloom for a good three to four weeks, beginning in early to mid-September.
This one involves just a wee bit of gardening, but you can handle it. All you need to do is plant it in neutral to slightly acidic soil that drains well, and keep it in dappled shade or somewhere it won’t get blasted by midday sun. Then keep the soil consistently moist.
You’ll be rewarded with outstanding, sharply lobed foliage and bee-loving, bottlebrush flowers. The standard A. racemosa features fragrant, bright white flowers that can hit 48” tall above the 24-30” green, mounded foliage. ‘Hillside Black Beauty’ has purplish-black foliage, with white flower spikes that, depending on growing conditions, will reach 4-7’. Plants can grow up to 36” wide before division is necessary.
Other varieties to look for are A. racemosa’Brunette’ which hangs in the same height range but with a pink tinge to the bloom, and purplish-bronze foliage. For you USDA Zone 5 visitors (cheaters!!), be on the lookout for a brand-new one, ‘Black Negligee’ (I just report ‘em, I don’t name ‘em) that features purplish foliage with a lavender tinge to the flower.
These are great perennials for the shade and woodland garden, or as native-looking transitional plants wandering off into the woods. The standard A. racemosa is hardy to Zone 3; ‘Brunette’ and ‘Hillside BB’ to Zone 4.
These plants have just recently been assigned to the genus Actea; after studying cell divisions and completing DNA analysis, plant experts discovered the plant has nothing in common with its formerly assigned genus, Cimicifuga. Yes, there are people on the planet who check out this stuff for a living.
Plant Spotlight Archive